# How to make a rectangular shape with inner boundary having the value of 1 and outer boundary a value of 0?

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waqas on 20 Dec 2021
Commented: waqas on 21 Dec 2021
Hi,
I am trying to make a rectangular shape with inner boundary value set as one and outer boundary value set as zero. Ideally a smoother transition from inner boundary to put boundary would be really helpful for my case. Following figure can explain the problem better:
In my implementation, I am struggling with the corners in particular with a linear transition from inner to outer boundary.
Following line should run the function to reproduce the the results of figure 2:
jQvals(Trow,Tcol,ouc,our,inc,inr,ptAbvCrk,ptBlwCrk,gridElems);
Relevant variable are in the attached mat file.
Looking forward to the feedback.
##### 3 CommentsShowHide 2 older comments
Matt J on 20 Dec 2021
Very good. Then see my answer below.

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### Accepted Answer

Matt J on 20 Dec 2021
Edited: Matt J on 20 Dec 2021
For example,
A=zeros(100);
A(30:70,30:70)=1;
A=max(0, 1-bwdist(A)/10);
A( abs( conv2(A,ones(3)/9,'same')-1)<=1e-6)=0;
imshow(A)
##### 6 CommentsShowHide 5 older comments
waqas on 21 Dec 2021
Worked like a charm with the first code that you shared using only the internal boundary. Thanks.

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